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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Oxycarbonylation des oléfines en présence de nitrites d'alkyle, catalysée par les complexes du palladium /

Brechot, Philippe, January 1900 (has links)
Th. univ.--Sci. pétrolières, spécialité chimie--Ecole nationale supérieure du pétrole et des moteurs et Paris 6, 1988. / 1989 d'après la déclaration de dépôt légal. Bibliogr. p. 137-143.
22

Synthesis and Application of PN3P Cobalt Pincer Complex for Selective Hydrogenation of Nitriles to Secondary Imines and α -Alkylation of Nitriles with Alcohols

Al Dakhil, Abdullah 07 1900 (has links)
Pincer complexes moieties have attracted much attention in the past years. They have been proved that they are highly active catalysts in many different known transition metal-catalyzed organic reaction and some unpredictable organic transformation. In this thesis, we will use PN3P Cobalt pincer complex in two different applications. The first application is the unpresented Cobalt-catalyzed hydrogenation of nitriles to secondary imines. The selective hydrogenation of nitriles into secondary imines is a very challenging task and the catalysts play a very important role in the reaction and the selectivity. Herein in the thesis, we report the first selective hydrogenation of nitriles to secondary imines catalyzed by a well-defined and accessible PN3P cobalt pincer complex. Our results show different selectivity compared with the known PNP cobalt catalytic system during the nitriles hydrogenation. A set of aliphatic and aromatic nitriles are hydrogenated to the secondary imine under relatively mild conditions. The second application is the alkylation of nitriles with alcohols using PN3P cobalt pincer complex. The alcohol is being used here as alkylating agent in state of using toxic alkyl halides or excess amount of base to avoid any salt waste. The cobalt pincer complex work as catalyst for transformation that undergoes alkylation via hydrogen transfer pathways. The beauty of this reaction that it is delver water as the only byproduct. A different nitriles and alcohol are tolerated in this reaction.
23

Sublethal Effects of Nitrite and Selenate on Two Species of Freshwater Fsh

Watenpaugh, Donald E. (Donald Edward) 08 1900 (has links)
Physiological and behavioral effects of exposure of fathead minnows (Pimephales promelas) and channel catfish (Ictalurus punctatus) to selenate-selenium (Se) and nitrite were investigated.
24

Antibacterial effects of nitrite in urine /

Carlsson, Stefan, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 4 uppsatser.
25

The nitrite ion : its role in vasoregulation and host defenses /

Björne, Håkan, January 2005 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.
26

Effect of reaction products from nitrite on Clostridium sporogenes in heated cured meats /

Roon, Pieter Simon van. January 1979 (has links)
Thesis--Rijksuniversiteit te Utrecht. / Summary in Dutch. Includes bibliographical references (p. 87-98).
27

Lethal and Sublethal Effects of Hemoxidants, Particularly Nitrite, on Selected Aquatic Animals

Huey, David W. (David Worley) 05 1900 (has links)
A research program was developed to investigate basic and applied aspects of toxicity, both lethal and sublethal, of hemoxidants, particularly nitrite, on fish, non-fish aquatic vertebrates, and crayfish. The major objectives of this research were to determine A) acute and sublethal toxicity of nitrite to selected aquatic organisms: 1. aquatic salamander larvae, Ambystoma texanum, 2. swamp crayfish, Procambarus simulans, 3. bluegill, Lepomis macrochirus, 4. bullfrog, tadpoles, Rana catesbiana, 5. channel catfish, Ictalurus punctatus, B) the influence of environmental chloride on acute and sublethal exposures to hemoxidants: 1. on acute nitrite toxicity to salamander larvae, crayfish, and bluegill, 2. on nitrite-induced methemoglobinemia in bullfrog tadpoles, Rana catesbian, C) the effect of environmental hydrogen ion concentrations (pH) on acute nitrite toxicity 1. to the crayfish, Procambarus simulans, 2. to the bluegill, Lepomis macrochirus, D) the effect of temperature in sublethal exposures to nitrite 1. methemoglobin formation in channel catfish exposed at different acclimation temperatures, 2. recovery from methemoglobinemia at different acclimation temperatures, E) the effect of the fish anesthetic TMS-222 on nitrite-induced methemoglobinemia in channel catfish 1. supression of nitrite-induced methemoglobinemia, 2. dose-response curve for TMS-222 induced methemoglobinemia, and F) if a methemoglobin reductase system is present in channel catfish.
28

Effects of sublethal nitrite concentrations on the metabolism of the sea bass, Lates calcarifer.

January 1989 (has links)
by Chiu Shui-fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 186-203.
29

Fermų aplinkos įtaka šulinių vandens kokybei, bei gyvulių sveikatingumui Linkuvos apylinkėse / Of farms influence of the environment of water in wells quality and of livestock wellness in neighborhood of Linkuva

Martyšiūtė, Laura 05 March 2014 (has links)
Ir nitritai ir nitratai tarnauja kaip svarbūs vandens kokybės indikatoriai. Augantis nitratų kiekis vandenyje yra daugiausia žemės ūkio trąšų naudojimo taip pat ir pramoninių procesų pasekmė. Nitratai vandenyje yra mažai nuodingi, tačiau antriniai mikrobakteriniai arba jų sumažėjimas gyvojoje sistemoje sukelia virsmą į nitritus, kurie jungiasi su hemoglobinu ir sukelia methemoglobinemiją Šiame darbe siekėme išsiaiškinti galimą vandens taršą fermų aplinkoje ir ar pasitaiko Linkuvos apylinkėse šulinių naudotojų gyvulių susirgimų atvejų, kurie būtų galimai sukelti girdant užterštu vandeniu. Tyrėme šachtinių šulinių vandenį, kuriame ieškojome nitratų, nitritų, fosfatų, amonio jonų, chloridų, sulfatų ir geležies kiekių nukrypimų. Rezultatai parodė, kad šachtinių šulinių vanduo nėra geros kokybės (n=16), visų tirtų mėginių (n=30) vanduo buvo labai kietas (100%). Ligos paprastai nėra registruojamos, dėl ekonominės situacijos Lietuvoje, todėl jai neskiriama pakankamai dėmesio. Darbo tikslas: Išsiaiškinti galimą vandens taršą fermų aplinkoje ir ar pasitaiko Linkuvos apylinkėse šulinių naudotojų gyvulių susirgimų atvejų, kurie galimai būtų sukelti girdant užterštu vandeniu. Darbo uždaviniai: 1. Išsiaiškinti surinktų šulinių vandens neatitikimus įstatymo (HN 24:2003) nuorodoms. 2. Nustatyti ar šachtinių šulinių vanduo yra kietas ir geros kokybės. 3. Išsiaiškinti ar gyventojai gerai įrengia šulinius, ar prižiūri jų aplinką. 4. Išaiškinti gyvulių ligų atvejus susijusius su girdomu... [toliau žr. visą tekstą] / Both nitrites and nitrates work as an important indicators of water quality. Rising nitrate levels in the water are mainly agricultural fertilizers as well as industrial processes result. Nitrates in water are low toxic, but secondary mikrobacterial or their decrease in the living system leads the conversion to nitrite, which binds to hemoglobin and causes methaemoglobinaemia. In this paper, we tried to find out the possible pollution of the environment of farms and if it occurs animal disease cases in the area of Linkuva, that would potentially lead to oral administration of contaminated water. We analyzed the mine wells, which were looking for nitrates, nitrites, phosphates, ammonium, chloride, sulphate and iron levels of variation. The results showed that the mine water is not of good quality (n = 16), all samples tested (n = 30) and showed that water was very solid (100%). Diseases are generally not recorded, due to the economic situation in Lithuania so it gets not enough attention.
30

Factors influencing natural attenuation of dinitrotoluenes in surface soils : badger army ammunition plants : a case study

Tulsiani, Urvi Kotak. January 2005 (has links)
Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2006. / Dr. Kurt Pennell, Committee Member; Dr. Jim Spain, Committee Member; Dr. Joseph Hughes, Committee Chair

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